diff --git a/apps/desktop/e2e/slash-command-menu.spec.ts b/apps/desktop/e2e/slash-command-menu.spec.ts
index 373c6c2482..7aae5a5828 100644
--- a/apps/desktop/e2e/slash-command-menu.spec.ts
+++ b/apps/desktop/e2e/slash-command-menu.spec.ts
@@ -78,7 +78,14 @@ test('compacts the active session', async ({
   await expect.poll(() => composer.textContent()).toBe('');
   await expect(page.getByText('压缩失败')).toHaveCount(0);
 
-  await composer.fill('after compact');
+  // After the compact completes the composer clears and can remount. `fill()`
+  // can land before the contentEditable is focused again, so the draft never
+  // populates and Enter submits nothing — the flake in issue #3289. Type
+  // through the focused element and require the draft to have settled before
+  // dispatching, mirroring the running-turn spec below.
+  await composer.click();
+  await composer.pressSequentially('after compact');
+  await expect.poll(() => composer.textContent()).toBe('after compact');
   await composer.press('Enter');
   await expect(page.getByText('Fake backend received: after compact')).toBeVisible();
   await expect(page.getByText('Fake backend received: /compact')).toHaveCount(0);
diff --git a/packages/computer-use/src/__tests__/maka-cu-service.test.ts b/packages/computer-use/src/__tests__/maka-cu-service.test.ts
index 89990f42ba..65b35bc34e 100644
--- a/packages/computer-use/src/__tests__/maka-cu-service.test.ts
+++ b/packages/computer-use/src/__tests__/maka-cu-service.test.ts
@@ -113,6 +113,7 @@ process.stdin.on('data', function (chunk) {
 let workDir = '';
 let mockPath = '';
 const services: MakaCuService[] = [];
+const imageDirs: string[] = [];
 
 function delay(ms: number): Promise<void> {
   return new Promise((resolve) => setTimeout(resolve, ms));
@@ -197,6 +198,7 @@ function makeService(
   };
   const service = new MakaCuService(options);
   services.push(service);
+  imageDirs.push(imageDir);
   return { service, logPath, imageDir };
 }
 
@@ -215,7 +217,24 @@ after(async () => {
       // A disposed service disposing again is not a test failure.
     }
   }
-  if (workDir) await rm(workDir, { recursive: true, force: true });
+  // `dispose()` is deliberately fire-and-forget: it SIGTERMs the child and
+  // schedules an asynchronous image-directory purge on child exit (or on the
+  // shutdown-grace SIGKILL, at most `shutdownGraceMs` = 3s later). Deleting
+  // `workDir` while those purges — and a child still flushing its ndjson log —
+  // are in flight races `rm` against concurrent writers and fails with
+  // ENOTEMPTY (issue #3290). Every `makeService` image directory is purged by
+  // its `dispose()`, so waiting for them to vanish is a "children exited and
+  // purges finished" barrier. The wait is tolerant rather than asserting —
+  // purge failures are permitted by contract ("the next spawn purges it
+  // again") and are not what this teardown tests — and the retrying `rm`
+  // backstop then only absorbs stragglers, not an unbounded race.
+  const purgeDeadline = Date.now() + 10_000;
+  while (imageDirs.some((imageDir) => existsSync(imageDir)) && Date.now() < purgeDeadline) {
+    await delay(25);
+  }
+  if (workDir) {
+    await rm(workDir, { recursive: true, force: true, maxRetries: 10, retryDelay: 100 });
+  }
 });
 
 describe('maka-cu supervisor: what the child may put on stdout', () => {